stm32f429的uart8 dma收发不能正常工作求解决办法？

发布于 2022-05-23 18:13:09 浏览：750 订阅该版

在rtt studio平台，芯片是stm32f429,串口3和串口4配置接收中断或者DMA模式都OK；串口8配置中断接收模式，收发都OK，但是配置成DMA模式该串口8不工作（发送和接收都没有）。
求助：将串口8配置成DMA收发模式可以正常工作。
![4.png](https://oss-club.rt-thread.org/uploads/20220523/5b8b36d1aa829944a1914f6804258c3b.png)
![1.png](https://oss-club.rt-thread.org/uploads/20220523/b8fa80b459036e4c7a741f7cdeb25121.png)
![2.png](https://oss-club.rt-thread.org/uploads/20220523/b2db73af394079b398a0a8684f33edd1.png)
![3.png](https://oss-club.rt-thread.org/uploads/20220523/af7ddb710188c81896a1c96df2062b8f.png)
```c
 /* 串口485方向GPIO设置 */
    rt_pin_mode(rs485_dir1, PIN_MODE_OUTPUT);
    rt_pin_write(rs485_dir1, PIN_LOW);

/* 查找串口设备 */
    u2_dev = rt_device_find("uart2");
    u3_dev = rt_device_find("uart3");
    u4_dev = rt_device_find("uart4");
    u8_dev = rt_device_find("uart8");
    /* 初始化信号量 */
    rt_sem_init(&rx2_sem, "rx2_sem", 0, RT_IPC_FLAG_FIFO);
    rt_sem_init(&rx3_sem, "rx3_sem", 0, RT_IPC_FLAG_FIFO);
    rt_sem_init(&rx4_sem, "rx4_sem", 0, RT_IPC_FLAG_FIFO);
    rt_sem_init(&rx8_sem, "rx8_sem", 0, RT_IPC_FLAG_FIFO);

/* 以读写及中断/DMA等发送接收方式打开串口设备 */
    rt_device_open(u2_dev, RT_DEVICE_FLAG_RDWR|RT_DEVICE_FLAG_INT_RX);
    rt_device_open(u3_dev, RT_DEVICE_FLAG_RDWR|RT_DEVICE_FLAG_DMA_RX|RT_DEVICE_FLAG_DMA_TX);
    rt_device_open(u4_dev, RT_DEVICE_FLAG_RDWR|RT_DEVICE_FLAG_DMA_RX|RT_DEVICE_FLAG_DMA_TX);
    rt_device_open(u8_dev, RT_DEVICE_FLAG_RDWR|RT_DEVICE_FLAG_INT_RX);
    /* 配置串口 */
    rt_device_control(u2_dev, RT_DEVICE_CTRL_CONFIG, (void *)&u2_configs);
    u3_configs.baud_rate = BAUD_RATE_9600;
    rt_device_control(u3_dev, RT_DEVICE_CTRL_CONFIG, (void *)&u3_configs);
    rt_device_control(u4_dev, RT_DEVICE_CTRL_CONFIG, (void *)&u4_configs);
    rt_device_control(u8_dev, RT_DEVICE_CTRL_CONFIG, (void *)&u8_configs);
    /* 设置接收回调函数 */
    rt_device_set_rx_indicate(u2_dev, uartx_rxCallback);
    rt_device_set_rx_indicate(u3_dev, uartx_rxCallback);
    rt_device_set_rx_indicate(u4_dev, uartx_rxCallback);
    rt_device_set_rx_indicate(u8_dev, uartx_rxCallback);
    /* 设置发送回调函数 */
    rt_device_set_tx_complete(u2_dev,uartx_txCallback);
    rt_device_set_tx_complete(u3_dev,uartx_txCallback);
    rt_device_set_tx_complete(u4_dev,uartx_txCallback);
    rt_device_set_tx_complete(u8_dev,uartx_txCallback);
    /* 设置接收数组 */
    rt_ringbuffer_init(&uart2_rxrb,uart2_rx_buffer,UART2_RX_Buffer_Len);
    rt_ringbuffer_init(&uart3_rxrb,uart3_rx_buffer,UART3_RX_Buffer_Len);
    rt_ringbuffer_init(&uart4_rxrb,uart4_rx_buffer,UART4_RX_Buffer_Len);
    rt_ringbuffer_init(&uart8_rxrb,uart8_rx_buffer,UART8_RX_Buffer_Len);
```

兜兜里有啥 2022-05-23

这家伙很懒，什么也没写！

兜兜里有啥 2022-05-23

这家伙很懒，什么也没写！

drv_usart.c文件中stm32_uart_get_dma_config只配置了uart1~6的DMA，uart7和uart8需要自己加一下
```c
static void stm32_uart_get_dma_config(void)
{
#ifdef BSP_USING_UART1
    uart_obj[UART1_INDEX].uart_dma_flag = 0;
#ifdef BSP_UART1_RX_USING_DMA
    uart_obj[UART1_INDEX].uart_dma_flag |= RT_DEVICE_FLAG_DMA_RX;
    static struct dma_config uart1_dma_rx = UART1_DMA_RX_CONFIG;
    uart_config[UART1_INDEX].dma_rx = &uart1_dma_rx;
#endif
#ifdef BSP_UART1_TX_USING_DMA
    uart_obj[UART1_INDEX].uart_dma_flag |= RT_DEVICE_FLAG_DMA_TX;
    static struct dma_config uart1_dma_tx = UART1_DMA_TX_CONFIG;
    uart_config[UART1_INDEX].dma_tx = &uart1_dma_tx;
#endif
#endif

#ifdef BSP_USING_UART2
    uart_obj[UART2_INDEX].uart_dma_flag = 0;
#ifdef BSP_UART2_RX_USING_DMA
    uart_obj[UART2_INDEX].uart_dma_flag |= RT_DEVICE_FLAG_DMA_RX;
    static struct dma_config uart2_dma_rx = UART2_DMA_RX_CONFIG;
    uart_config[UART2_INDEX].dma_rx = &uart2_dma_rx;
#endif
#ifdef BSP_UART2_TX_USING_DMA
    uart_obj[UART2_INDEX].uart_dma_flag |= RT_DEVICE_FLAG_DMA_TX;
    static struct dma_config uart2_dma_tx = UART2_DMA_TX_CONFIG;
    uart_config[UART2_INDEX].dma_tx = &uart2_dma_tx;
#endif
#endif

#ifdef BSP_USING_UART3
    uart_obj[UART3_INDEX].uart_dma_flag = 0;
#ifdef BSP_UART3_RX_USING_DMA
    uart_obj[UART3_INDEX].uart_dma_flag |= RT_DEVICE_FLAG_DMA_RX;
    static struct dma_config uart3_dma_rx = UART3_DMA_RX_CONFIG;
    uart_config[UART3_INDEX].dma_rx = &uart3_dma_rx;
#endif
#ifdef BSP_UART3_TX_USING_DMA
    uart_obj[UART3_INDEX].uart_dma_flag |= RT_DEVICE_FLAG_DMA_TX;
    static struct dma_config uart3_dma_tx = UART3_DMA_TX_CONFIG;
    uart_config[UART3_INDEX].dma_tx = &uart3_dma_tx;
#endif
#endif

#ifdef BSP_USING_UART4
    uart_obj[UART4_INDEX].uart_dma_flag = 0;
#ifdef BSP_UART4_RX_USING_DMA
    uart_obj[UART4_INDEX].uart_dma_flag |= RT_DEVICE_FLAG_DMA_RX;
    static struct dma_config uart4_dma_rx = UART4_DMA_RX_CONFIG;
    uart_config[UART4_INDEX].dma_rx = &uart4_dma_rx;
#endif
#ifdef BSP_UART4_TX_USING_DMA
    uart_obj[UART4_INDEX].uart_dma_flag |= RT_DEVICE_FLAG_DMA_TX;
    static struct dma_config uart4_dma_tx = UART4_DMA_TX_CONFIG;
    uart_config[UART4_INDEX].dma_tx = &uart4_dma_tx;
#endif
#endif

#ifdef BSP_USING_UART5
    uart_obj[UART5_INDEX].uart_dma_flag = 0;
#ifdef BSP_UART5_RX_USING_DMA
    uart_obj[UART5_INDEX].uart_dma_flag |= RT_DEVICE_FLAG_DMA_RX;
    static struct dma_config uart5_dma_rx = UART5_DMA_RX_CONFIG;
    uart_config[UART5_INDEX].dma_rx = &uart5_dma_rx;
#endif
#ifdef BSP_UART5_TX_USING_DMA
    uart_obj[UART5_INDEX].uart_dma_flag |= RT_DEVICE_FLAG_DMA_TX;
    static struct dma_config uart5_dma_tx = UART5_DMA_TX_CONFIG;
    uart_config[UART5_INDEX].dma_tx = &uart5_dma_tx;
#endif
#endif

#ifdef BSP_USING_UART6
    uart_obj[UART6_INDEX].uart_dma_flag = 0;
#ifdef BSP_UART6_RX_USING_DMA
    uart_obj[UART6_INDEX].uart_dma_flag |= RT_DEVICE_FLAG_DMA_RX;
    static struct dma_config uart6_dma_rx = UART6_DMA_RX_CONFIG;
    uart_config[UART6_INDEX].dma_rx = &uart6_dma_rx;
#endif
#ifdef BSP_UART6_TX_USING_DMA
    uart_obj[UART6_INDEX].uart_dma_flag |= RT_DEVICE_FLAG_DMA_TX;
    static struct dma_config uart6_dma_tx = UART6_DMA_TX_CONFIG;
    uart_config[UART6_INDEX].dma_tx = &uart6_dma_tx;
#endif
#endif
}
```